NASA hopes to launch the much-delayed space telescope on Halloween to investigate the secrets of the early universe.
One wing of the James Webb Space Telescope's main mirror opens into place during a final test of the mirror deployment system in May 2021.
In a press briefing, NASA and Northrop Grumman -- the primary contractor on the project -- said the next-generation telescope is on track to launch this year.
During the update, the JWST team said testing of the telescope components and rehearsals of launch and deployment events have gone well.
NASA and the European Space Agency's iconic and old Hubble Space Telescope is still holding on, but has faced many technical difficulties over recent years. .